1. Grading based on crystal morphology and location of flaws
Generally divided into the positive crystal, distorted crystal, serpihan segitiga, hubungi kristal kembar, dan bentuk agregat. Diantara mereka, the business is divided into:
Batu: Mengacu pada berlian berkualitas tinggi 1 karat.
Fancy Colours: The color of these diamonds does not include colorless with blue or yellow tints, but refers to bright and bright Fancy Colours such as blue, hijau, warna kuning jernih, coklat dan mawar.
Batu tertutup: Single crystal with a nice shape for sawing and polishing.
Batu berbintik: Kristal tunggal, nice shape, tidak terlalu murni (noda berat), but they can be removed when cutting.
Nat: Distorsi kristal, should be cleaved or cut directly.
Batu tidak beraturan: mempunyai bentuk oktahedral atau dodecahedral tidak beraturan dan dapat langsung dipotong.
Batu yang bisa dibelah: Diamonds that should be cleaved.
Batu berlapis: Berlian ini memerlukan pemikiran, as they are surrounded by a rough coat. Unveiled they may still be dim, but they may also be a gem.
Batu buram: Mirip dengan batu berlapis, except that the coat is now translucent.
Batu susu: Seperti namanya, batu-batu ini memiliki penampilan putih susu.
Blok: have a special shape and it is difficult to see their crystal orientation.
Tempat: These diamonds are usually twin and are often used for rose cuts.
Pasir: Mengacu pada berlian yang sangat kecil (kurang dari 0.10 karat), used for type 8/8 pemotongan.
Barang milik bersama: The quality of these diamonds has been mediocre and is on the limit of gem-quality diamonds.
Batu penolakan: Diamonds of unqualified quality for the jewelry industry should be excluded.
2. Classification of crystal surface features
Umumnya, according to the depth and size of the triangular pits on the crystal surface and whether there may be stress cracks, it is divided into excellent, Bagus, medium, and poor.
3. Crystal color grading
Biasanya, warnanya tidak berwarna, putih susu, hijau muda, kuning, kuning muda, hitam, cokelat, dll.. Diantara mereka, light green diamonds are the most gambled. Umumnya, batu telanjang berwarna tinggi dapat muncul. berjudi. Diantara mereka, berlian kuning dan coklat dibagi menjadi kuning, kuning muda, putih dan putih cemerlang.
4. Grading of crystal size
Generally divided into 0.5ct, 1ct, 2ct, dll., it is divided into small stone, middle stone, large stone, and extra large stone.
5. Grading of crystal clarity
Umumnya, it is divided into defect grade, heavy defect grade, and clean grade with 10 times magnifying glass under special lamps.